The period when humans chipped away at rocks to make sharp edges used for cutting and scraping. They used these and made spears and axes.

Which of these are part of the three-age system identifying periods by tool manufacture and use?

Bronze is made up of two materials. Which are these?

During this period, metals were used. People combined copper and tin to make tools in this age.

The composition of steel are these two:

This was a time in early human history when people began using tools and weapons made of iron. This age started and ended at different times in different places.

The time before people invented writing is called ___________.

Also called "Old Stone Age" and the time when people lived in caves, under rock overhangs, or out in the open. Tools were used to hunt animals. They gathered wild plants to eat and moved with the seasons to find food.

Also called "New Stone Age" and the time when people ground and polished stones for more useful tools. They learned to grow crops and tame animals. They settled in villages.